Prasat is located some 40km from the Thai Cambodian border. The Chong Chom / Osmach border is becoming known for its friendliness and efficiency. If you have to do a visa-run, then I recommend this border crossing. A Cambodian visa costs 1000B and there is an additional 300B charge if you have to leave the same day. This will take in all 15-20 minutes from the Thai side to returning back to the Thai soil, and is a considerably nicer experience than the Aranyaprathet / Poi Pet crossing which is the busiest and most infamous.

Kap Chueng immigration is 10km from the Chong Chom if you need an immigration office, where there reputation is very friendly.

If you are intending to keep going it’s the ideal way to get to Seam Reap (Angkor Watt), there are plenty of taxi’s waiting to take you where you want to go, and at the time of writing 1800B seems to the going rate, but with the world price of oil going up, this is liable to increase.